Development of a portable electronic nose for in‐situ detection of submerged fermentation of Tremella aurantialba

The aim of this study was to develop a portable electronic nose (e‐nose) system for the rapid and convenient detection of saponin in submerged fermentation of Tremella aurantialba ( T. aurantialba ) in situ . The system was built using hardware and software systems. The hardware system consisted of a gas path module and a circuit module, and the software framework provided a friendly human–computer interface and multivariate computational tools. Subsequently, the e‐nose system was used to detect off‐gas in fermentation tanks every 12 hr in situ . Saponin content was simultaneously determined by the traditional measurement method. On the basis of odor data from the e‐nose, partial least squares regression (PLSR) was used to establish a quantitative model for the prediction of saponin content. For the PLSR model, the root mean square error of prediction ( RMSEP ) was 0.2247 and the correlation coefficients of prediction ( Rp ) were 96.76% in the prediction set. These results showed that the feasibility of the device designed to detect the fermentation degree of the process and proved to be a valuable tool for real‐time and in‐situ detection of the fermentation process of T. aurantialba .